Two major experiments will be conducted in the upcoming year to investigate effect that aging has upon selective attention. In the first, the speed with which young and elderly subjects search a multi-colored array of digits for a target will be measured. The effect that prior information regarding the color of the target has upon search time will indicate how effectively young and elderly persons can restrict their processing (focus their attention) to only the relevant portions of the array. The second study will examine the effect that extensive practice with the same target has upon the ability of young and old persons to form an "automatic detection response" in which search no longer requires attention. The strength of the detection response thus formed will be assessed in the two age groups by using this previous target as a distractor (non-target) in a new search task with the same subjects.